Automatic brake-adjuster



Nb Modl.)

J. B. BURNS.

AUTOMATIC B'RAKE'ADJUSTER. No. 352,444. Patented Nov. 9, 1886.

E 9 ii UNITED STATE PATENT OFFICE.

JOHN B. BURNS, OF INDIANAPOLIS, INDIANA, ASSIGNOR OF ONE-HALF TO' ELISHA D. EAMES, OF WATERTOWN, NEW YORK.

AUTOMATIC BRAKE-ADJUSTER.

' SPECIFICATION forming part of Letters Patent No. 352,444, dated November 9, 1886.

Application filed February 10, 1886. Serial No. 191,410. (No model.)

To aZZ whom it may concern.-

Be it known that I, JOHN B. BURNS, of the city of Indianapolis, county of Marion, and State of Indiana, have invented certain new and useful Improvements in Automatic Brake- Adjusters, of which the following is a specification. I

As is well known, brake-shoes wear rapidly in use. Power-brakes necessarily have alim- IO ited movement, and consequently, in order to compensate for the Wear of the brake-shoes, the connections between the diaphragm or cylinder of the power-brake and the brake-bar are necessarily continually taken up. To do I 5 this by hand is a laborious and irksome task, owing to the difficulty of getting under the cars to the proper place, and requires constant watchfulness and care, which are often lacking on the part of those iutrusted to perform this duty. It is therefore desirable that some means should be provided by which as the brake-shoes wear the connections may be automatically adjusted accordingly, and this is the object of my invention. Said object is ac-, 2 5 complished by providing in the rods, to which the lower ends of the brake-levers are connected, slots in which said ends may travel, and ratchet-teeth with which detents and a pawl may engage, as will be hereinafter more particularly describedand claimed.

Referring to the accompanying drawings, which are made a part hereof, and on which similar letters of reference indicate similar parts, Figure 1 is an end elevation of a pair 3 5 of car-Wheels and the brakes therefor, illustrating my invention, a portion of the truck-frame being shown to indicate the relation of parts; Fig. 2, a detail perspective view of a portion of the brake-lever and the rod by which said brake-lever is connected to the other brakelever, being the parts which particularly illus- I trate my invention; Fig. 3, a View looking downwardly from the dotted ine 3 3 in Fig. 4; Fig. 4, a longitudinal vertical section on the dotted line4 4 in Figs. 3, 5, and 6; Fig. 5, a

horizontal sectional view looking downwardly from the dotted line 5 5 in Figs. 4 and 6; and Fig. 6 a transverse vertical section on the dotted line 6 6 in Figs. 3, 4, and 5.

In said drawings, the portions marked A represent portions of the car-truck frame; B, the car-wheels; O, brake-beams suspended by rods or links a to said truck-frame; D D, the brake-levers; E, the rod connecting them, and

F the rod connecting the upper end of one of said brake-levers to the diaphragm, piston, winding-staff, or whatever the brake is to be operated by.

The truck-frame A, car-wheels B, brakebeams O, and the brake-shoes c c thereon are or may be of any ordinary or desired construction, and will not be further described herein, except incidentally in describing the invention.

The brake-levers are arranged in substantially the usual manner, one, D, being pivoted to the trucl -frame at one end and to the rod E at the other, and carrying the brake-beam in the usual manner. The other, D, is also generally formed similar to the usual brake- 7o lever, supports a brake-beam, and is connected to the operating-rod F in the usual manner. At its lower end, however, instead of being pivoted directly to the rod E, the pivot-bolt 01 passes through a slot in said rod and through detents d, secured outside of said rod. 'lhese detents are formed preferably of spring-steel, and their shape is indicated most plainly in Figs. 3 and 5. Their forward or engaging ends are formed thick and stout, while the rear ends are made thinner to act as springs, andthey are bowed out somewhat at the point Where the pivot-bolt d passes through them, so as to permit the necessary operation of the spring portions. lVhere the spring portions come in 8 5 contact with the rods they are provided with projections 10, as shown in Fig. 6, which e20. tend into the slots and keep the detents in place. The lever is also provided with a pawl, d secured just above the rod E by a pivot, 0 d", and a spring, d, may be secured thereto and rest against said pawl to insure the proper operation thereof. I

The rod E is the usual connecting-rod between the brake-levers, and is preferably slot- 5 ted in two directions. The vertical slot receives the lower end of the brake-lever D, and the horizontal slot receives the bolt d, which passes through the lower end of said lever. The sides and top of this slotted portion are The notches in the top of the rod E are formed of such length that the lever D in moving back and forth will not operate the pawl to engage therewith, until, by reason of wear in the brake-shoes, its stroke is made longer than arranged for in the primary adjustment of the brake mechanism. As soon as this occurs, this brake-lever in moving forward when the power is applied will pass the notch in which it has been working and enter the next notch, and when the power is released and the brakes drop away from the wheels the rearward motion of-this le-ver will carry the detents d forward, so that they will engage with the next notch, and thus the slack will be automatically taken up, and the power of the brakes will be the same as before, notwithstanding the worn condition of the brake-shoes.

It will be noticed that the power required to take up the slack consequent upon the worn condition is exerted during the letting off of the brakes, and consequently does not use any of the power required in setting them.

It-will be unders'tood, of course, that th ratchet and pawl and detent arrangement shown may be varied in construction and arrangement. The brake-lever, instead of the rod, might beslotted; or the parts might be soarrangements of parts and withinthe scope of my invention. The spring d might, and probablywill in many cases, be dispensed with, as gravity alone is usually sufficient to operate the pawl; but the addition of a spring lends additional certainty to the operation, and the arr-angementshownisdeemed by me, all things considered, as probably the best and as preferable.

Having thus fully described my-said invention, what I claim as new, and desire to secure byLetters Patent, is-

1. The combination, in a brake mechanism, of a serrated connecting-rod and a brake-lever engaging with said rod, provided with one or more detents as a means of engagement, and a pawl by which the engagement may be varied.

2. The combination of aslotted rod, E, having serrations upon its sides and top, a brakelever passingbetween the two portions of said rod, detents outside of said rod, secured to the lower end of said lever by a pivot-bolt, and a pawl also secured to saidlever above said rod.

3. The combination, in abrake mechanism,

of a rod, E, having vertical and horizontal slots and serrations, as described, a brake-lever, D, entering the vertical slot in said rod. a pivot-bolt, d, passing through the lower end of said lever and through the horizontal slot in said rod, detents d on the outer ends of said bolt, and a pawl, d secured to said brake-lever, said detents and said pawl being arranged to engage with the serrations in said rod.

4. The combination, in a brake mechanism, of the brake levers, a rod connecting said brake-levers, and a connection between one of said brake-levers and the operating devices, the lower end of said brake-lever being connected to said connecting-rod by a ratchet and pawl and detent, substantially'as and for the purposes set forth.

5. The combination, in a brake mechanism, of brake-levers, a rod connecting said levers, means of operating said levers, and a ratchet, pawl, and-detent connection between thelower end of said brake-lever and said rod.

6. The combination, in a brake mechanism, of a brake-lever, a rod to which said brakelever is connected, a ratchet-and-pawl con-nec- 4 tion between said brake-lever and said rod and detents, said detents being provided with projections p,which enter slots in said rod and hold said detents in position, substantially as set forth. a

In witness whereof I have hereunto set my hand andseal, at Indianapolis,Indiaua,this 5th day of February, A. D. 1886.

JOHN B. BURNS. [1,. -s.]

In presence of- I O. BRADFORD, E. D. EAMES. 

